1 /* Licensed under LGPLv2.1+ - see LICENSE file for details */
4 #include <ccan/typesafe_cb/typesafe_cb.h>
5 #include <ccan/time/time.h>
12 extern bool io_plan_for_other;
13 extern bool (*io_debug)(struct io_conn *conn);
14 #define io_plan_other() ((io_plan_for_other = true))
16 #define io_plan_other() (void)0
19 struct io_state_read {
24 struct io_state_write {
29 struct io_state_readpart {
34 struct io_state_writepart {
40 * struct io_plan - returned from a setup function.
42 * A plan of what IO to do, when.
46 /* Only NULL if idle. */
47 bool (*io)(int fd, struct io_plan *plan);
48 /* Only NULL if closing. */
49 struct io_plan (*next)(struct io_conn *, void *arg);
53 struct io_state_read read;
54 struct io_state_write write;
55 struct io_state_readpart readpart;
56 struct io_state_writepart writepart;
61 * io_new_conn - create a new connection.
62 * @fd: the file descriptor.
63 * @plan: the first I/O function.
64 * @finish: the function to call when it's closed or fails.
65 * @arg: the argument to @finish.
67 * This creates a connection which owns @fd. @plan will be called on the
68 * next io_loop(), and @finish will be called when an I/O operation
69 * fails, or you call io_close() on the connection.
71 * Returns NULL on error (and sets errno).
73 #define io_new_conn(fd, plan, finish, arg) \
74 (io_plan_other(), io_new_conn_((fd), (plan), \
75 typesafe_cb_preargs(void, void *, \
79 struct io_conn *io_new_conn_(int fd,
81 void (*finish)(struct io_conn *, void *),
85 * io_new_listener - create a new accepting listener.
86 * @fd: the file descriptor.
87 * @init: the function to call for a new connection
88 * @arg: the argument to @init.
90 * When @fd becomes readable, we accept() and pass that fd to init().
92 * Returns NULL on error (and sets errno).
94 #define io_new_listener(fd, init, arg) \
95 io_new_listener_((fd), \
96 typesafe_cb_preargs(void, void *, \
100 struct io_listener *io_new_listener_(int fd,
101 void (*init)(int fd, void *arg),
105 * io_close_listener - delete a listener.
106 * @listener: the listener returned from io_new_listener.
108 * This closes the fd and frees @listener.
110 void io_close_listener(struct io_listener *listener);
113 * io_write - queue data to be written.
114 * @data: the data buffer.
115 * @len: the length to write.
116 * @cb: function to call once it's done.
119 * This will queue the data buffer for writing. Once it's all
120 * written, the @cb function will be called: on an error, the finish
121 * function is called instead.
123 * Note that the I/O may actually be done immediately.
125 #define io_write(data, len, cb, arg) \
126 io_write_((data), (len), \
127 typesafe_cb_preargs(struct io_plan, void *, \
128 (cb), (arg), struct io_conn *), \
130 struct io_plan io_write_(const void *data, size_t len,
131 struct io_plan (*cb)(struct io_conn *, void *),
135 * io_read - queue buffer to be read.
136 * @data: the data buffer.
137 * @len: the length to read.
138 * @cb: function to call once it's done.
141 * This will queue the data buffer for reading. Once it's all read,
142 * the @cb function will be called: on an error, the finish function
145 * Note that the I/O may actually be done immediately.
147 #define io_read(data, len, cb, arg) \
148 io_read_((data), (len), \
149 typesafe_cb_preargs(struct io_plan, void *, \
150 (cb), (arg), struct io_conn *), \
152 struct io_plan io_read_(void *data, size_t len,
153 struct io_plan (*cb)(struct io_conn *, void *),
158 * io_read_partial - queue buffer to be read (partial OK).
159 * @data: the data buffer.
160 * @len: the maximum length to read, set to the length actually read.
161 * @cb: function to call once it's done.
164 * This will queue the data buffer for reading. Once any data is
165 * read, @len is updated and the @cb function will be called: on an
166 * error, the finish function is called instead.
168 * Note that the I/O may actually be done immediately.
170 #define io_read_partial(data, len, cb, arg) \
171 io_read_partial_((data), (len), \
172 typesafe_cb_preargs(struct io_plan, void *, \
173 (cb), (arg), struct io_conn *), \
175 struct io_plan io_read_partial_(void *data, size_t *len,
176 struct io_plan (*cb)(struct io_conn *, void *),
180 * io_write_partial - queue data to be written (partial OK).
181 * @data: the data buffer.
182 * @len: the maximum length to write, set to the length actually written.
183 * @cb: function to call once it's done.
186 * This will queue the data buffer for writing. Once any data is
187 * written, @len is updated and the @cb function will be called: on an
188 * error, the finish function is called instead.
190 * Note that the I/O may actually be done immediately.
192 #define io_write_partial(data, len, cb, arg) \
193 io_write_partial_((data), (len), \
194 typesafe_cb_preargs(struct io_plan, void *, \
195 (cb), (arg), struct io_conn *), \
197 struct io_plan io_write_partial_(const void *data, size_t *len,
198 struct io_plan (*cb)(struct io_conn *, void*),
203 * io_idle - explicitly note that this connection will do nothing.
205 * This indicates the connection is idle: some other function will
206 * later call io_read/io_write etc. (or io_close) on it, in which case
209 struct io_plan io_idle(void);
212 * io_timeout - set timeout function if the callback doesn't fire.
213 * @conn: the current connection.
214 * @ts: how long until the timeout should be called.
216 * @arg: argument to @cb.
218 * If the usual next callback is not called for this connection before @ts,
219 * this function will be called. If next callback is called, the timeout
220 * is automatically removed.
222 * Returns false on allocation failure. A connection can only have one
225 #define io_timeout(conn, ts, fn, arg) \
226 io_timeout_((conn), (ts), \
227 typesafe_cb_preargs(struct io_plan, void *, \
231 bool io_timeout_(struct io_conn *conn, struct timespec ts,
232 struct io_plan (*fn)(struct io_conn *, void *), void *arg);
235 * io_duplex - split an fd into two connections.
236 * @conn: a connection.
237 * @plan: the first I/O function to call.
238 * @finish: the function to call when it's closed or fails.
239 * @arg: the argument to @finish.
241 * Sometimes you want to be able to simultaneously read and write on a
242 * single fd, but io forces a linear call sequence. The solition is
243 * to have two connections for the same fd, and use one for read
244 * operations and one for write.
246 * You must io_close() both of them to close the fd.
248 #define io_duplex(conn, plan, finish, arg) \
249 (io_plan_other(), io_duplex_((conn), (plan), \
250 typesafe_cb_preargs(void, void *, \
255 struct io_conn *io_duplex_(struct io_conn *conn,
257 void (*finish)(struct io_conn *, void *),
261 * io_wake - wake up an idle connection.
262 * @conn: an idle connection.
263 * @plan: the next I/O function for @conn.
265 * This makes @conn do I/O the next time around the io_loop().
267 #define io_wake(conn, plan) (io_plan_other(), io_wake_((conn), (plan)))
268 void io_wake_(struct io_conn *conn, struct io_plan plan);
271 * io_break - return from io_loop()
272 * @ret: non-NULL value to return from io_loop().
273 * @plan: I/O to perform on return (if any)
275 * This breaks out of the io_loop. As soon as the current @next
276 * function returns, any io_closed()'d connections will have their
277 * finish callbacks called, then io_loop() with return with @ret.
279 * If io_loop() is called again, then @plan will be carried out.
281 #define io_break(ret, plan) (io_plan_other(), io_break_((ret), (plan)))
282 struct io_plan io_break_(void *ret, struct io_plan plan);
284 /* FIXME: io_recvfrom/io_sendto */
287 * io_close - terminate a connection.
288 * @conn: any connection.
290 * The schedules a connection to be closed. It can be done on any
291 * connection, whether it has I/O queued or not (though that I/O may
292 * be performed first).
294 * It's common to 'return io_close(...)' from a @next function, but
295 * io_close can also be used as an argument to io_next().
297 struct io_plan io_close(struct io_conn *, void *unused);
300 * io_loop - process fds until all closed on io_break.
302 * This is the core loop; it exits with the io_break() arg, or NULL if
303 * all connections and listeners are closed.
306 #endif /* CCAN_IO_H */